From mboxrd@z Thu Jan 1 00:00:00 1970 From: AL-KERNEL To: kernel-cve@kernelcve.org Subject: [CVE-2026-97516][LOW] wifi: rtw88: Add NULL check for chip->edcca_th in rtw_fw_adaptivity_result() [ Upstream Date: Thu, 24 Sep 2026 18:38:09 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-AL-KERNEL-CVE: CVE-2026-97516 X-AL-KERNEL-Priority: LOW X-AL-KERNEL-Severity: LOW X-AL-KERNEL-Base-Severity: LOW X-AL-KERNEL-KPANIC: NO X-AL-KERNEL-ActionableScore: 1 X-AL-KERNEL-ActionableScore-Lower: unknown X-AL-KERNEL-Commit: 6fa23cafaf30f4877e357f8eebcff00dff4aa9cb List-Id: CVE: CVE-2026-97516 Priority: LOW AL-KERNEL base severity: LOW KPANIC flag: NO Patch: wifi: rtw88: Add NULL check for chip->edcca_th in rtw_fw_adaptivity_result() [ Upstream Commit: 6fa23cafaf30f4877e357f8eebcff00dff4aa9cb Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=6fa23cafaf30f4877e357f8eebcff00dff4aa9cb Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-97516 Analysis date: Thu, 24 Sep 2026 18:38:09 -0400 ActionableScore: 1 ActionableScore lower bound: unknown Actionable bucket: Ordinary Moderate Manual review required: NO Summary: No one-sentence report phrase was found. ====================================================================== ABOUT THIS REPORT ====================================================================== The original Linux kernel CVE announcement for CVE-2026-97516 is available here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-97516 The original announcement does not normally provide a security severity estimate, CVSS assessment, or enough information to determine whether the reported kernel bug represents a practically relevant security issue. This report was generated by AL-KERNEL, an AI-assisted Linux kernel vulnerability analysis system developed by Alexander Larkin. It combines an autonomous classifier with LLM-assisted technical analysis and a separate ActionableScore mechanism. The purpose of this report is to prioritize Linux kernel CVEs before manual review, identify cases that require prompt investigation, and support automatic closure of issues that are unlikely to have meaningful security impact. Published priority for this report: LOW Manual review required: NO A detailed explanation of the methodology and priority rules is included at the end of this message. ====================================================================== AL-KERNEL CLASSIFICATION RESULT ====================================================================== CVE-2026-97516 LOW https://www.kernelcve.org/list/?q=CVE-2026-97516 CHECK WITH IMPACT FROM ORIG NN MODERATE Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H';**CWE-476;CWE-754;Other CVSS 'AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:L';BEST CVSS score: '5.5';DESCR 'A NULL pointer dereference in the rtw88 firmware adaptivity result handler occurs when an affected Realtek 8821CE device has no edcca_th configuration and the driver processes an adaptivity result event. This can cause a kernel Oops and may result in loss of wireless functionality or a host denial of service when Oops handling is configured to panic. The patch context does not establish that an unauthenticated wireless peer can directly generate this firmware event. For the CVSS the PR:L rating is used for the paranoid score because a local user or limited capability service may be able to indirectly cause wireless device activity, although reliable triggering may normally require administrative control of the interface. No confidentiality or integrity impact is supported because the patch shows a NULL dereference and not a memory corruption primitive.';NO MANUAL CHECK; ,and ActionableScore result is Ordinary Moderate (with actual score 1) YES REMOTE OOB NULLPTR NETWORK HARDWARE LINUS DECREASED_TO_MODERATE_REGULAR_FROM_MODERATE7_BASED_ON_GUESSCVSS_AND_CIANNH DECREASED_TO_LOW_FROM_MODERATE_BASED_ON_ACTIONABLESCORELESSTHAN3 NO NO checked ====================================================================== ACTIONABLESCORE ANALYSIS ====================================================================== ActionableScore=1 PrimitiveClass=CLASS_C RealUAF=NO HostAdminRequired=UNKNOWN NamespaceScopedPrivilege=UNKNOWN ImportantCandidate=NO ManualReview=NO AutoDowngradeAllowed=YES 1. ActionableScore * Raw conservative score: 1 * Conservative score: 1 * Raw paranoid score: 1 * Paranoid score: 1 * Final recommended bucket: **Ordinary Moderate**:: 2. Signal breakdown * +1 Kernel Oops and availability impact. The patch directly documents a NULL pointer dereference and resulting kernel Oops on affected Realtek 8821CE devices. This can disrupt the driver and wireless service. A host panic is possible only when Oops handling is configured accordingly, so no additional host-wide DoS point is awarded. Important non-awarded signals: * No UAF, stale lifetime reference, double release, refcount mutation, OOB access, or use of freed storage is established. * No controlled reclaim, arbitrary write, attacker-controlled target, callback influence, or structured post-free object consumption is established. * No confidentiality or integrity point is awarded. The patch shows a NULL dereference only. * Remote reachability is not established. The vulnerable handler processes a firmware C2H adaptivity result event, but the supplied evidence does not show that an external wireless peer can directly cause that event. * Local unprivileged reachability is not established. The supplied prior assessment suggests possible indirect WiFi activity, but does not prove that an ordinary local user can reliably trigger the complete path. * No host-admin penalty is applied because host-admin-equivalent privilege is not positively established. * No hardware rarity penalty is applied. The issue is limited to 8821CE hardware, but that alone does not prove rare or physical-only attacker access. 3. Reachability analysis The affected path is in the rtw88 firmware event handling path and requires an affected Realtek 8821CE wireless device whose chip information does not define edcca_th. The immediate trigger is a firmware adaptivity result event processed by rtw_fw_adaptivity_result. The supplied patch does not establish whether this event occurs during normal device initialization, channel activity, scanning, association, firmware recovery, or another device state transition. It also does not establish that a remote WiFi peer can send a frame that directly causes firmware to generate this event. Host-admin-equivalent privilege is not proven necessary, but below-host-admin reachability is also not proven. Therefore HostAdminRequired=UNKNOWN. No namespace-specific capability path is shown, and the complete trigger chain is not known to be namespace-scoped. The hardware prerequisite is an affected 8821CE device. No race, repeated attacker-controlled lifecycle operation, special sysctl, boot setting, or prior privileged configuration is established by the supplied evidence. 4. Primitive and severity interpretation The exact primitive is a NULL pointer dereference of chip edcca_th in rtw_fw_adaptivity_result. This is an invalid-state dereference, not a lifetime, ownership, refcount, or memory-corruption primitive. There is no active structured stale object, no fixed stale storage, and no concrete repeated release or refcount operation. The patch adds an early return when edcca_th is NULL. The demonstrated consequence is a kernel Oops and potential driver or host availability impact depending on Oops configuration. The issue is classified as CLASS_C because the demonstrated behavior is crash or DoS-like invalid-pointer behavior without an independently useful corruption primitive. Privilege escalation, confidentiality impact, integrity impact, remote exploitation, and arbitrary memory access are speculative and are not supported by the patch. ImportantCandidate=NO because no meaningful exploitation leverage beyond the NULL dereference and resulting Oops is established. AutoDowngradeAllowed=YES because there is no unresolved UAF, active-object corruption, authorization bypass, ownership violation, or concrete repeated lifetime mutation requiring preservation for manual security analysis. Likely operational severity is low. Affected systems may experience wireless driver disruption or, in configurations that panic on Oops, host denial of service. 5. One-sentence report phrase A NULL pointer dereference in the rtw88 firmware adaptivity result handler can cause a kernel Oops on affected Realtek 8821CE devices, with no demonstrated remote trigger, memory corruption, confidentiality impact, integrity impact, or privilege escalation path. 6. Manual review recommendation NO MANUAL CHECK NEEDED The patch establishes a hardware-specific NULL dereference and Oops only. No concrete corruption, lifetime, ownership, authorization, or attacker-controlled firmware-input primitive is shown. 7. Call-site confidence Call-site confidence: medium ====================================================================== UPSTREAM PATCH SUMMARY ====================================================================== Patch: wifi: rtw88: Add NULL check for chip->edcca_th in rtw_fw_adaptivity_result() [ Upstream Commit: 6fa23cafaf30f4877e357f8eebcff00dff4aa9cb Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=6fa23cafaf30f4877e357f8eebcff00dff4aa9cb Changed files: drivers/net/wireless/realtek/rtw88/fw.c Diff excerpt: Not included in this email. See the upstream URL for the full patch. Full patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=6fa23cafaf30f4877e357f8eebcff00dff4aa9cb ====================================================================== DETAILED REPORT METHODOLOGY ====================================================================== The original Linux kernel CVE announcement for CVE-2026-97516 can be found here: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-97516 The original CVE announcement normally does not include a security-level estimate. In particular, it may not contain a CVSS assessment, an impact level, or enough information to determine whether the reported bug is a practically relevant security issue. One purpose of this parallel CVE list is to provide that missing technical and prioritization information. The original goal of the AL-KERNEL project was to prioritize Linux kernel CVE analysis automatically before manual review. The system can also help identify non-security issues that may be suitable for automatic closure. This report was generated by AL-KERNEL, an AI-assisted Linux kernel vulnerability analysis system developed by Alexander Larkin. The first analysis stage combines an autonomous classifier with additional LLM-based analysis. The autonomous classifier runs locally on a CPU and is based on a backpropagation neural network. Together, these mechanisms produce a technical vulnerability description, identify likely weakness types, estimate CVSS severity, and provide input for ActionableScore. Two CVSS estimates are retained because incomplete kernel vulnerability information often permits more than one defensible interpretation: Conservative CVSS vector: AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:L The Best / paranoid CVSS vector: AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H The Best / paranoid CVSS score: 5.5 The conservative vector represents a lower-impact interpretation. The Best/paranoid vector intentionally represents a plausible upper-bound interpretation and should not automatically be treated as demonstrated real-world impact. CVSS may also need to be adjusted for a particular Linux deployment, because actual reachability, privileges, enabled kernel configuration, hardware, namespaces, exposed device nodes, and other environmental conditions can differ significantly between systems. A separate ActionableScore mechanism evaluates practical remediation urgency. Its analysis may include reachability, attack prerequisites, subsystem exposure, memory-corruption characteristics, denial-of-service reliability, and possible confidentiality, integrity, or privilege-escalation impact. Conservative ActionableScore: unknown Paranoid ActionableScore: 1 The final base severity is taken directly from the second tab-separated field of the AL-KERNEL classification result. ActionableScore does not replace or independently override that final AL-KERNEL decision, and if ActionableScore adjusted impact level of ALKERNEL, then you would see self-readable flags above like INCREASED_TO_HIGH_BASED_ON_ACTIONABLESCOREHIGHEREQTHAN7. For an AL-KERNEL result of MODERATE, this report uses the following additional presentation split: ActionableScore below 5 -> MODERATE REGULAR ActionableScore 5 or more -> MODERATE 7.0 The distinction between MODERATE REGULAR and MODERATE 7.0 makes it possible to identify Moderate issues that should receive manual analysis and fixes before lower-priority MODERATE REGULAR issues. In many cases, MODERATE REGULAR fixes may wait for a later rebase or routine update. There is one override in which MODERATE REGULAR becomes MODERATE 7.0 even when the ActionableScore is below 5. When the AL-KERNEL result contains the KPANIC flag, a MODERATE result is always presented as MODERATE 7.0. The KPANIC flag selected with few regexps without usage of AI at all, so it helps to detect cases when Kernel Crash happens and similar (to filter False-Negative results from the LLM usage). KPANIC indicates that a reliable kernel crash, kernel panic, or similarly serious kernel availability impact was identified by the classification workflow. AL-KERNEL base severity for this report: LOW KPANIC detected for this report: NO Published priority for this report (same as in Subject): LOW These results are intended to support engineering triage. They are machine-generated estimates, and cases marked for manual review should be validated by a human security engineer before final disposition. For more info read docs linked from here: https://kernelcve.org/ (and you can submit you own patch there to generate such a report for non-existant CVE-id yet). Note that in many cases this AI tool selects higher severity, than real is (means you can expect Importants instead of Moderate 7.0 or Moderates 7.0 instead of regular Moderates). If you see such cases, please use reply email interface to add additional manual analyses info to this particular CVE. And please, please, let me know when you see Lows instead of Importants or Important instead of Low (because particular for such cases I need to tune this AI tool to make it better for this one and next similar). My contact email for such notifications is alexanjelausa@gmail.com (and both send reply to CVE record itself too and see "reply" button below for howto reply).